Device for imparting reciprocatory motion to a moving element

ABSTRACT

A device for imparting reciprocatory motion to a moving element by means of a driven rotor having a channel formed around the outer periphery, a channel follower driven by the rotor and an impact absorbing means acting on the channel follower to decelerate it as it completes its movement in one direction and accelerate it during its initial movement in the opposite direction.

United States Patent [191 Espasa 1 Sept. 25, 1973 DEVICE FOR IMPARTING RECIPROCATORY MOTION TO A MOVING ELEMENT [76] Inventor: Arcadio Espasa, Calle Peligro 40,

Barcelona, Spain [22] Filed: Aug. 5, 1971 [21] Appl. No.: 169,342

[30] Foreign Application Priority Data Aug. 28, 1970 Spain 383161 52 US. Cl. 74757, 242/18 R [51] Int. Cl. Fl6h 25/12 [58] Field of Search 74/57; 242/18 R [56] 3 References Cited UNITED STATES PATENTS I 1,399,107 12/1921 Frankowski et a1. 74/57 2,441,596 5/1948 Reitter 74/57 3,190,628 6/1965 Litzka 74/57 3,398,904 8/1968 Adams et a1... 74/57 1,959,606 5/1934 Zindel .1 242/18 R 7/1965 Hambach 242/18 R Primary Examiner-Charles J. Myhre Assistant ExaminerWesley S. Ratliff, Jr. Atl0rneyGranvil1e' M.. Brumbaugh et a1.

[57] ABSTRACT A device for imparting reciprocatory motion to a mov-' ing element by means of a driven rotor having a channel formed around the outer periphery, a channel follower driven by the rotor and an impact absorbing means acting on the channel follower to decelerate it as it completes its movement in one direction and accelerate it during its initial movement in the opposite direction.

2 Claims, 8 Drawing Figures PATENTED'SEPZS I975 Ii nm FIG. 2

FIG. 4

I N VEN TOR.

ARCADIO ESPASA PATENTEDSEPZS I975 SHEET 3 BF 4 INVENTOR. ARCADIO ESPAS'A DEVICE FOR IMPARTING RECIPROCATORY MOTION TO A MOVING ELEMENT This invention relates to a device for imparting reciprocatory motion to a moving element wherein it is desired to quickly decelerate the movable element as it completes its travel in one direction and to accelerate it during the initial motion in the opposite direction with minimum impact and friction.

The present invention has particular application to certain types of mcahines in which it is desired to impart an alternating or reciprocatory motion at substantially uniform and constant velocity over as much of the travel in eachdirection as is possible. One such application of the present invention is for imparting reciprocatory motion to a thread guide for cross-winding thread onto a bobbin. In such machines it is desirable that the thread guide move at relatively uniform and constant velocity in each direction and to reverse direction as quickly as possible. Ideally, the change in direction should be accomplished almost instantaneously, but the devices heretofore proposed to accomplish a rapid change in direction have been characterized by excessive impact and friction, especially at high speeds of operation.

The object of the present invention is to provide a device for imparting reciprocatory motion to a moving element capable of quickly decelerating the speed at the completion of one stroke and accelerating the speed at the beginning of the stroke in the opposite direction with minimum impact and friction. Toward this end, the device of the present invention embodies a driven rotor having a channel formed around the outer periphery, a channel follower connected to the member to which the reciprocatory motion is to be imparted and impact absorbing means acting on the channel follower to decelerate it rapidly as it completes its stroke in one direction and to accelerate up to the desired velocity as it begins its stroke in the opposite direction.

For a complete understanding of the present invention reference can be made to the detailed description which follows and to the accompanying drawings, in

which:

FIG. 1 is a plan view of the device of the present invention;

FIGS 2 and 3 are sectional viewstaken on the lines 2-2 and 3-3, respectively, of Figure 1, looking in the direction of the arrows;

FIG. 4 is a plan view illustrating an alternative embodiment of the invention;

FIGS. 5A, 5B and 5C are schematic views showing the channel follower near the end of one stroke, at the point of reversal and at the beginning of the return stroke; and

FIG. 6 is a plan view of another alternative embodiment of the invention.

Referring to the drawings, the present invention is shown as applied to a device for imparting reciprocatory motion to a thread guide 10 having an eyelet 11 which reciprocates over a distance d between the ends of a bobbin 12 on which the thread is being crosswound. The thread passes through the eyelet-as it is wound onto the bobbin.

The reciprocatory motion is imparted to the thread guide 10 by a driven rotor 13 having a channel 14 formed around the outer periphery and'a channel follower 15 carried by a support 15a which is mounted on a reciprocating tube 16 in telescoping relation with a guide rod 17. The driven rotor 13 and the channel follower 15 are accommodated within a housing 18, and the rod 17 is supported at one end by a bracket 19 which extends outwardly from one side of the housing. The tubular element 16 is guided in its reciprocatory motion on the rod 17 within openings 20 in the hous- The bobbin 12 is held between a pair of tapered supports 21 and 22, the support 21 being mounted at the end of a drive shaft 23 and the support 22 being mounted at the end of a plunger 24 and urged into operative engagement with the bobbin by a spring 25. R0- tation is imparted to the spool by a belt driven pully 26 mounted on the opposite end of the shaft 23.

The driven rotor 13 is mounted on a shaft 27 which is also driven at the proper speed by the pulley 26 through a gear 28 mounted on the shaft 23 anda gear 29 mounted on the shaft 27. I

The channel 14 includes a section for moving the channel follower 15 at a relatively uniform and constant velocity in one direction and a section for moving the channel follower at a relatively uniform and constant velocity in the opposite direction. Intermediate these two sections the channel follower is quickly decelerated at the end of the travel in one direction and quickly accelerated at the start of its travel in the opposite direction so that the reversal will occur as quickly as possible with a minimum of impact and friction.

The means for accomplishing the reversal in direction of the channel follower is illustrated schematically in FIGS 5A, 5B, and 5C of the drawings. In FIG. 5A, the channel follower 15, shown in its preferred form as a rhombus, is guided between the channel walls 30 and 31 .approaching the end of the travel in one direction. At the section of the channel at which the reversal occurs the outer wall 30 of the channel is provided with an opening 32 to permit the channel follower to engage in impact absorbing element 33, in this instance a spring, which absorbs the impact of the change in direction and quickly decelerates the channel follower at the terminal end of its movement in one direction and thereupon accelerates the channel follower at the beginning of its movement in the opposite direction.

When the channel follower reaches the opening 32 in the channel wall 30, as shown in FIG. 58, it engages the spring 33 and begins its movement in the opposite direction, initially engaging a channel wall section 30a which is resiliently mounted at the leading end of the return section of the channel by means of a resilient mounting or spring 34. The resiliently mounted channel wall section 30a absorbs part of the impact of the channel follower as it begins its return movement and makes it possible to replace the part of the channel wall which is subject to the greatest wear. The channel follower is quickly accelerated to the desired uniform velocity, as shown in FIG. 5C.

The channel follower 15 can be of circular or ovaloid section, but in the preferred shape of a rhombus it adapts to the shape and change in direction of the channel. At the point of reversal the two opposite edges to be guided by the return section of the channel are presented to the return section before the other two opposite guided edges leave the previous section of the channel, as illustrated in FIG. 5B.

Instead of providing an opening 32 in the channel wall 30, the width of the channel can be enlarged at this point to afford the channel follower sufficient displacement to enable it to impart the impact to the resilient element 33. Also, the channel follower need not directly engage the resilient element 33. In the embodiment illustrated in FIG. 4, the support a for the channel follower engages blocks of resilient material at each end of the stroke.

To afford a rapid reversal of the reciprocating parts, it is desirable that the inertia of the movable parts be reduced to a minimum. Although the inertia of the hollow tube 16 in the embodiment illustrated in FIG. 1 is relatively small, in the embodiment illustrated in FIG. 6 the overall length of the reciprocating tube 16, and hence the inertia, is substantially reduced. In this embodiment the channel follower support 15a slides on a shaft 36 mounted at opposite ends in the housing 18. The movable support 15a carries an arm 37 which is connected with a part 38 clamped to the tubular element 16.

The means for absorbing the impact of reversal in the embodiment illustrated in FIG. 6 includes cupshaped elements 39 mounted to opposite inner walls of the housing 18, each containing a plurality of elastic washers 40 of the Belleville or Schnorr type and having a plastic end collar 41 which receives the impact of the channel follower support 15a at the end of the stroke.

The present invention has been shown in its preferred forms and by way of example only, and many modifications and variations may be made within the spirit of the invention. The invention, therefore, is not to be limited to any particular form or embodiment except insofar as such particular forms or embodiments are expressly set forth in the claims.

I claim:

1. A device for imparting reciprocatory motion to a moving element comprising a driven rotor, a continuous channel carried by the driven rotor and formed around the outer periphery thereof, a channel follower engaging said channel and connected to the memeber to which the reciprocatory motion is imparted, one part of the channel imparting motion to the channel follower in one direction and another part of the channel imparting motion to the channel follower in the opposite direction, the two parts of the channel intersecting at an angle requiring the channel follower to change direction abruptly in passing from one part to the other, an open zone in the outer wall of the channel between the two parts thereof, and resilient impact absorbing means mounted in position to be aligned with said opening on each revolution of the driven rotor to enable the channel follower to engage the impact absorbing means through the opening at the end of the stroke of the channel follower whereby each time the channel follower passes from one part of the channel to the other the resilient impact absorbing means decelerates the channel follower as it completes its movement in one direction and accelerates its movement in the opposite direction.

2. A device for imparting reciprocatory motion to a moving element comprising a driven rotor, a continuous channel carried by the driven rotor and formed around the outer periphery thereof, a channel follower engaging said channel and connected to the member to which the reciprocatory motion is imparted, one part of the channel imparting motion to the channel follower in one direction and another part of the channel imparting motion to the channel follower in the opposite direction, the two parts of the channel intersecting at an angle requiring the channel follower to change direction abruptly in passing from one part to the other, and open zone in the outer wall of the channel between the two parts thereof, a tubular element connecting the channel follower and the moving element and a guide rod in telescoping engagement with an end of the tubular element to support it for reciprocatory motion. 

1. A device for imparting reciprocatory motion to a moving element comprising a driven rotor, a continuous channel carried by the driven rotor and formed around the outer periphery thereof, a channel follower engaging said channel and connected to the memeber to which the reciprocatory motion is imparted, one part of the channel imparting motion to the channel follower in one direction and another part of the channel imparting motion to the channel follower in the opposite direction, the two parts of the channel intersecting at an angle requiring the channel follower to change direction abruptly in passing from one part to the other, an open zone in the outer wall of the channel between the two parts thereof, and resilient impact absorbing means mounted in position to be aligned with said opening on each revolution of the driven rotor to enable the channel follower to engage the impact absorbing means through the opening at the end of the stroke of the channel follower whereby each time the channel follower passes from one part of the channel to the other the resilient impact absorbing means decelerates the channel follower as it completes its movement in one direction and accelerates its movement in the opposite direction.
 2. A device for imparting reciprocatory motion to a moving element comprising a driven rotor, a continuous channel carried by the driven rotor and formed around the outer periphery thereof, a channel follower engaging said channel and connected to the member to which the reciprocatory motion is imparted, one part of the channel imparting motion to the channel follower in one direction and another part of the channel imparting motion to the channel follower in the opposite direction, the two parts of the channel intersecting at an angle requiring the channel follower to change direction abruptly in passing from one part to the other, and open zone in the outer wall of the channel between the two parts thereof, a tubular element connecting the channel follower and the moving element and a guide rod in telescoping engagement with an end of the tubular element to support it for reciprocatory motion. 